130818-21-2Relevant academic research and scientific papers
Continuous Electrochemical Synthesis of Iso-Coumarin Derivatives from o-(1-Alkynyl) Benzoates under Metal- and Oxidant-Free
Lin, Xinxin,Fang, Zheng,Zeng, Cuilian,Zhu, Chenlong,Pang, Xinyan,Liu, Chengkou,He, Wei,Duan, Jindian,Qin, Ning,Guo, Kai
supporting information, p. 13738 - 13742 (2020/10/02)
A non-oxidant and metal-free strategy for synthesizing iso-coumarin by using a continuous electrochemical microreactor to initiate an oxidative cyclization reaction of o-(1-alkynyl) benzoate and radicals. This efficient and clean continuous electrosynthesis method not only avoids the complicated gas protection operation and production of by-products in the batch processes, but also help to overcome the difficulty that batch metal catalysis and electrocatalysis are difficult to scale up, and has the potential for pilot-scale experiment.
Metal-Free Synthesis of 4-Chloroisocoumarins by TMSCl-Catalyzed NCS-Induced Chlorinative Annulation of 2-Alkynylaryloate Esters
Norseeda, Krissada,Chaisan, Nattawadee,Thongsornkleeb, Charnsak,Tummatorn, Jumreang,Ruchirawat, Somsak
, p. 16222 - 16236 (2019/12/25)
4-Chloroisocoumarins can be conveniently prepared from 2-alkynylaryloate esters via the activation of alkynes by electrophilic chlorine, generated in situ from N-chlorosuccinimide (NCS) in the presence of 10 mol % trimethylsilyl chloride (TMSCl), which leads to 6-endo-dig-selective chlorinative annulation to give the desired products in moderate to quantitative yields. The procedure employs readily available reagents and can be conveniently carried out on a wide scope of substrates under mild conditions (0 °C to rt). Furthermore, the reaction is scalable for gram-scale preparation of 4-chloroisocoumarins. Additionally, 4-bromo- and 4-iodoisocoumarins can be prepared in moderate to good yields by replacing NCS with N-bromosuccinimide (NBS) and N-iodosuccinimide (NIS), respectively.
Silver triflate/: P -TSA co-catalysed synthesis of 3-substituted isocoumarins from 2-alkynylbenzoates
Gianni, Jonathan,Pirovano, Valentina,Abbiati, Giorgio
, p. 3213 - 3219 (2018/05/17)
In this paper, we describe the silver triflate/p-toluenesulfonic acid co-catalysed synthesis of seventeen isocoumarins and two thieno[2,3-c]pyran-7-ones starting from 2-alkynylbenzoates and 3-alkynylthiophene-2-carboxylates, respectively. The reaction proceeds with absolute regioselectivity under mild reaction conditions and low catalyst loading, to afford the desired products in good to excellent yields. A conceivable reaction mechanism is proposed and supported by isotope-exchange tests, 1H NMR studies and ad hoc experiments.
Palladium(II)-catalyzed tandem annulation reaction of o-alkynylbenzoates with methyl vinyl ketone for the synthesis of isocoumarins
Wang, Huan,Han, Xiuling,Lu, Xiyan
, p. 8626 - 8631 (2013/09/12)
A palladium(II)-catalyzed highly regioselective tandem reactions of o-alkynylbenzoates with methyl vinyl ketone for the synthesis of isocoumarins was developed. It is a convenient, mild and environmentally benign reaction with moderate to high yield. The
Tuning selectivity of anionic cyclizations: Competition between 5-exo and 6-endo-dig closures of hydrazides of o-acetylenyl benzoic acids and based-catalyzed fragmentation/recyclization of the initial 5-exo-dig products
Vasilevsky, Sergey F.,Mikhailovskaya, Tat'yana F.,Mamatyuk, Victor I.,Salnikov, Georgy E.,Bogdanchikov, Georgy A.,Manoharan, Mariappan,Alabugin, Igor V.
supporting information; experimental part, p. 8106 - 8117 (2010/03/04)
(Chemical Equation Presented) Depending on the reaction conditions and the nature of substituents at the triple bond, anionic cyclizations of hydrazides of o-acetylenyl benzoic acids can be selectively directed along three alternative paths, each of which
Transmission of Polar Effects. Part 21. Alkaline Hydrolysis of the 2'- and 4'-substituted 2-Methoxycarbonyldiphenylacetylenes and (Z)-2'- and -4'- Substituted 2-Methoxycarbonylstilbenes and the Ionisation and Esterification, with Diazodiphenylmethane of t
Bowden, Keith,Ghadir, Khalaf D. F.
, p. 1333 - 1338 (2007/10/02)
The rate coefficients for the alkaline hydrolysis of a series of 2'- and 4'-substituted 2-methoxycarbonyldiphenylacetylenes and (Z)-2-methoxycarbonylstilbenes have been determined in 70percent (v/v) dimethyl sulphoxide-water at both 30.0 and 50.0 deg C an
